*{margin:0;padding:0}
.center{
    margin-left: auto;
    margin-right: auto;
}
body{
    font-family: -apple-system,SF UI Text,Arial,PingFang SC,Hiragino Sans GB,Microsoft YaHei,WenQuanYi Micro Hei,sans-serif;
    color:#333;
}
.row:after{
    content:"";
    display: table;
    clear:both;
}
a{
    text-decoration: none;
    color:#333;
}
table{
    border-collapse: collapse;
}